1. Field of the Invention
This invention relates to systems and methods for removing electronic components, such as microchips, from substrates.
2. Background of the Invention
High-end microelectronic modules often include one or more microchips mounted to a carrier to provide a desired level of performance and functionality. Often, one or more microchips on a carrier substrate need to be replaced to repair and/or improve the performance of a microelectronic module. When removing a microchip, the solder on the carrier pads underneath the microchip also typically needs to be removed so that another microchip can be attached.
Several techniques currently exist for removing solder from carrier pads or other parts of a substrate. One technique involves utilizing a porous metal block to remove solder from a substrate. Such a porous metal block may include protrusions that are placed in contact with molten solder on the substrate to absorb the solder through capillary action. The porous metal block may be designed with an interconnected and uniform porosity that provides uniform absorption across the block surface. The number and dimensions of the protrusions on the block may vary based on the application. Although effective, this technique can be costly and time-consuming.
Another technique is to use an acid such as nitric acid to dissolve the solder on the carrier. For example, the solder may be removed by dipping the substrate in fuming nitric acid. Unfortunately, such a technique can contaminate the substrate surface and may be difficult to implement for chip removal. Furthermore, acids such as nitric acid can be hazardous and difficult to handle. Nitric acid in particular is corrosive, reactive, and dangerous to touch or inhale.
In view of the foregoing, what are needed are systems and methods to remove electronic components, such as microchips, from carrier substrates. Ideally, such systems and methods would be effective to remove most if not all of the solder that connects the electronic components to the substrates. Such systems and methods would also ideally not require chemicals such as fluxes or cleaning agents to remove the solder.